Chapter 1: An Introduction to the Human Body

Anatomy and Physiology

Human Anatomy

The study of the body’s structures

Gross Anatomy

Study of larger structures of the body, visible to the naked eye

Microscopic Anatomy

Study of structures that can only be observed with a microscope

Regional Anatomy

Study of specific regions of the body by specific parts or areas

Systemic Anatomy

Study of the body by specific organ systems

Physiology

Study of the chemistry and physics of the structures of the body

Homeostasis

Process by which a living thing keeps its inside steady even when the world outside changes

Structural organization of the human body

Chemical, cell, tissue, organ, organ system, organism level

Integumentary System

Encloses internal body structures, site of many sensory receptors

Integumentary System includes

Hair, skin, nails

Skeletal System

Supports the body, enables movement with muscular system

Skeletal System includes

Cartilage, bones, joints

Muscular System

Helps maintain body temperature, enables movement with skeletal system

Muscular System includes

Skeletal muscles, tendons

Nervous System

Detects and processes sensory information, activates bodily responses

Nervous System includes

Brain, spinal cord, peripheral nerves

Endocrine System

Secretes hormones, regulates bodily processes

Endocrine System includes

Pituitary gland, thyroid gland, pancreas, adrenal glands, testes/ovaries

Cardiovascular System

Delivers oxygen and nutrients to tissues, equalizes temperature in the body

Cardiovascular System includes

Heart, blood vessels

Lymphatic System

Returns fluid to blood, defends against pathogens

Lymphatic System includes

Thymus, lymph nodes, spleen, lymphatic vessels

Respiratory System

Removes carbon dioxide, delivers oxygen to blood

Respiratory System includes

Nasal passage, trachea, lungs

Digestive System

Processes food for use by the body, removes wastes from undigested foods

Digestive System includes

Stomach, liver, gall bladder, large intestine, small intestine

Urinary System

Controls water balance, removes wastes from blood and excretes them

Urinary System includes

Kidneys, urinary bladder

Reproductive System

Male and female produces sex hormones and gametes

Energy

Can neither be created nor destroyed, only change form

Metabolism

Sum of all anabolic and catabolic reactions that occur simultaneously

Anabolism

Process where smaller molecules are combined into larger substances that uses energy

Catabolism

Process where larger substances are broken down into smaller molecules and releases energy

Adenosine triphosphate (ATP)

Primary energy currency of all living cells, it stores and releases energy

Responsiveness

Ability of an organism to adjust to changes in its internal and external environment

Development

All of the changes the body goes through in life

Differentiation

In which unspecialized cells become specialized in structure and function to perform certain tasks in the body

Growth

Increase in body size, increasing number of existing cells

Reproduction

The formation of a new organism from parent organisms

Without reproduction

Death will come to all complex organisms and the line of organisms would end

Requirements for human life

Oxygen, nutrients, narrow range of temperature and atmospheric pressure

Negative feedback (regular response)

A self regulating control system that detects a change in the body and reverses it to return conditions back to normal

Positive Feedback (only when body needs)

Intensifies a change in the body’s physiological condition rather than reversing it

Anatomical position

Is that of the body standing upright, with the feet at shoulder width and parallel, toes forward

Prone

Face down orientation of body

Supine

Face up orientation of body

Anterior (ventral)

describes the front or direction toward the front of the body

Posterior (dorsal)

describes the back or direction toward the back of the body

Superior (cranial)

describes a position above or higher than another part of the body proper

Inferior (caudal)

describes a position below or lower than another part of the body proper

Lateral

describes the side or direction toward the side of the body

Medial

describes the middle or direction toward the middle of the body

Proximal

describes a position in a limb that is nearer to the point of attachment or the trunk of the body

Distal

describes a position in a limb that is farther from the point of attachment or the trunk of the body

Superficial

describes a position closer to the surface of the body

Deep

Describes a position farther from the surface of the body

Section

A two dimensional surface of a three dimensional structure that has been cut

Plane

imaginary two dimensional surface that passes through the body

Sagittal Plane

Plane that divides the body or organ vertically into right and left pieces

Frontal plane (coronal plane)

plane that divides the body or an organ into an anterior (front) and a posterior (rear) portion

Transverse Plane

plane that divides the body or organ horizontally into upper and lower portions

Oblique Plane

Intersects the body at an angel and is not parallel or perpendicular

Dorsal (posterior) cavity and ventral (anterior) cavity

are the largest body compartments and contain delicate internal organs

Cranial cavity

houses the brain (posterior)

Spinal cavity (vertebral cavity)

encloses the spinal cord (posterior)

Thoracic cavity (ventral/anterior cavity)

enclosed by the rib cage (contains lung and heart)

Abdominopelvic cavity (ventral/anterior cavity)

largest cavity in the body

Serous membrane (serosa)

thin membranes that cover the walls and organs in the thoracic and abdominopelvic cavities, meant to cushion and reduce friction of organs)

Pleura

the serous membrane that encloses the pleural cavity, surrounds the lungs

Pericardium

serous membrane that encloses the pericardial cavity, surrounds the heart

Peritoneum

serous membrane that encloses the peritoneal cavity, surrounds several organs in abdominopelvic cavity

X-ray

a form of electromagnetic radiation used primarily to visualize hard body structures

Computed Tomography CT

non invasive imaging technique that uses computers to analyze several cross sectional x-rays

Magnetic Resonance Imaging MRI

non invasive medical imaging technique that creates detailed images of organs and soft tissues inside the body

Positron Emission Tomography PET

a medical imaging technique that can illustrate physiologic activity of the organ(s)

Ultrasonography

an imaging technique thats the least invasive mostly used in situations such as pregnancy